Locomotives traditionally include a car body that houses one or more power units of the locomotive. The weight of the car body is supported at either end by trucks that transfer the weight to opposing rails. The trucks typically include cast steel or fabricated frames that provide a mounting for traction motors, axles, and wheel sets. Longitudinal traction links typically extend along horizontal sides of the truck and transfer tractive forces between the frame and the car body. Each railway truck is configured to pivotally support a base platform of the car body by way of a common bolster. Locomotives can be equipped with trucks having two, three, or four axles.
In some situations, operation of the locomotive can be less than optimal due to poor transfer of weight between axles due to traction and/or braking forces. In particular, when the locomotive is stationary, the weight on each axle is configured to be approximately equal. During operation, however, as the locomotive brakes, accelerates, and/or turns, forces can transfer from one axle to another, resulting in different axles carrying unequal loads. Wheels carrying lighter loads can lose proper traction and therefore be vulnerable to slipping. Accordingly, the varying loads on different axles can reduce the durability, stability, and reliability of the truck.
Force transfer can result from numerous factors related to the truck. For example, a significant amount of force transfer can be attributed to the location of the traction links. The traction links transfer tractive forces between the frame and the car body and typically extend horizontally along the sides of the truck. An example of a four-axle articulated locomotive truck with this configuration is disclosed in U.S. Pat. No. 4,485,743 that issued to Roush et al. (“Roush”) on Dec. 4, 1984. The traction links in Roush are pivotally connected to the truck frame and preferably placed as low as possible near the track.
Although sufficient for many applications, the traction links disclosed in Roush may be less than optimal. This is because the low level nature of the traction links can generate forces causing the frame to pitch and therefore result in undesirable force transfer between axles. Furthermore, space constraints may not permit low level placement of the traction links in all applications.
The railway truck of the present disclosure solves one or more of the problems set forth above and/or other problems in the art.